This invention relates to a control system for an engine speed meter and more particularly to an improvement in bar-type speed displays.
In many types of machines, it is desirable to provide an indication of the speed at which the machine is operating. When the machine comprises an internal combustion engine that propels a vehicle such as a watercraft in addition to watercraft speed or in leu of it, it is very desirable to provide an indication of speed at which the engine is running. This permits the operator to insure that the engine is operating within its desired speed range and also at the optimum condition for fuel consumption. One type of speed indicator which has a great value is the bar-type speed indicator.
With a bar-type speed indicator, the display includes a plurality of segments each representative of a respective speed range of the engine. As the engine speed increases, an increasing number of the segments is illuminated so as to indicate the actual speed of the engine. Although this type of display is desirable, it has some disadvantages.
First, although the display indicates the engine speed, it is desirable to provide a warning indication when the engine speed is not at a desired speed. For example, it may be desirable to provide a display that indicates a warning when the engine speed is operating at below the desired engine speed and hence may approach a stalling condition.
It is, therefore, a principal object to this invention to provide an improved bar-type speed indicator with a warning system.
It is a further object to this invention to provide an improved and simplified warning arrangement for a bar-type speed display for indicating when the engine speed is not at a desired speed.
Another disadvantage with bar-type speed displays is because each segment is indicative of a speed range, it may be difficult for the operator to use the bar-type display to set an actual exact speed for the engine. For example, it is desirable to permit the operator to adjust the engine so as to establish the desired idle speed. However, when the speed display is of the bar-type, the idle speed is only a single speed within a range of one of the display elements. Hence, the operator cannot actually set the desired idle speed but can only set the speed within a certain range unless one of the extreme ends of the display range coincides with the desired engine speed.
It is therefore, a still further object to this invention to provide an improved bar-type tachometer that will permit the operator to set an exact engine speed.
It is a further object to this invention to provide a bar-type tachometer that will provide a display indicative of a certain exact engine speed.